Source code for langchain.output_parsers.regex
from __future__ import annotations
import re
from typing import Dict, List, Optional
from langchain_core.output_parsers import BaseOutputParser
[docs]class RegexParser(BaseOutputParser[Dict[str, str]]):
"""Parse the output of an LLM call using a regex."""
@classmethod
def is_lc_serializable(cls) -> bool:
return True
regex: str
"""The regex to use to parse the output."""
output_keys: List[str]
"""The keys to use for the output."""
default_output_key: Optional[str] = None
"""The default key to use for the output."""
@property
def _type(self) -> str:
"""Return the type key."""
return "regex_parser"
[docs] def parse(self, text: str) -> Dict[str, str]:
"""Parse the output of an LLM call."""
match = re.search(self.regex, text)
if match:
return {key: match.group(i + 1) for i, key in enumerate(self.output_keys)}
else:
if self.default_output_key is None:
raise ValueError(f"Could not parse output: {text}")
else:
return {
key: text if key == self.default_output_key else ""
for key in self.output_keys
}